Sedimentation coefficient distributions of cold water-extracted glycogens of Fasciola hepatica.

Extraction of glycogen from rabbit liver and from Ascaris muscle at low temperatures and without the use of alkali or acid yields a product, the sedimentation characteristics of which differ considerably from those of glycogen isolated by more drastic procedures (1). Glycogen extracted with cold water not only exhibits a markedly higher weight average sedimentation coefficient, but also a much greater polydispersity. This polydisper&y is characterized by two more or less distinct regions of sedimentation coefficients. An attempt was made to determine whether rapid changes in the glycogen concentration of a given organism or tissue affect these two regions daerentially. To this end, the sedimentation coefficient distributions of glycogens from the parasitic trematode, the liver fluke, Fusciola heputica, were examined under conditions which alter the total glycogen concentration of the organism. This parasite was selected because its glycogen content is influenced readily by the presence or absence of glucose in the medium in which the organism is incubated (2). It was found that changes in the total glycogen content were associated with much greater variations in the concentration of the heavier component than in that of the lighter fraction.